The tower facing First Street will be the second highest structure in the city. The tower facing Mission Street will be the home of the city's first Waldorf Astoria hotel.

"Today is a very exciting day for both our company and the city of San Francisco," Oceanwide Center CEO Chen Wu said in a statement. "We look forward to giving the city a project that will be a source of pride for all San Franciscans."

The center will be a mix of offices, condominiums and the hotel.

It will also incorporate two historic buildings at 78 and 88 First Street, both of which will offer office and retail space.

The First Street tower will be 910 feet and 61 stories high. It will include 109 luxury homes from the 41st to 61st floors and about 1 million square feet of office space from the seventh to 40th floors. The Mission Street tower will be 625 feet and 54 stories tall and home to 156 luxury homes, the Waldorf Astoria, a spa, bar and restaurant.

The condominiums in the First Street tower will be the highest in San Francisco.

The architects have planned for 26,000 square feet of public space, the pinnacle of which will be a public square or urban plaza adjacent to First Street.

Swinerton and Webcor are the builders. Swinerton is known for the construction of the San Francisco Opera House and the Fairmont Hotel.

The project is scheduled for completion by 2021. Mayor Edwin Lee, Supervisor Jane Kim and others attended the groundbreaking.